Headers and trans crossmember question

Discussion in 'Lowered & Street Systems' started by WesN, Oct 10, 2018.

  1. WesN

    WesN Junior Member

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    0AB3C360-2833-4E0D-ADC8-86A4A9BE7F97.jpeg BBE58BE9-6CDE-4174-B17E-D5E878BC3DFF.jpeg On my 81 shorty 2wd I install a set of Hooker Comp long tube headers from a 72 Monte Carlo/Chevelle. They fit nice and clear the mounts and frame nice BUT the pass side outlet lines up right in the middle of the trans crossmember. The drivers side is fine because the crossmember drops down to clear what was the old pellet cat converter and the outlet will clear over it. The headers are close to even with the frame so would be good on bagged units.
    Now my question is has anybody used or come across a bolt in crossmember that the exhaust will clear? My other option was to get another like I have and cut the drop side off (drivers) and weld it to the stock one (pass side) so it will drop under the frame on both sides.
     
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  2. bucket

    bucket Super Moderator Staff Member

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    On mine (also using car headers), I used S-bend collector reducers and mildly restructured the crossmember on that side. I also ditched the diagonal brace.
     
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  3. Rusty Nail

    Rusty Nail Build the wall - deport them all!

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    Cut that end of the crossmember off, turn it upside down and re-weld it?
     
  4. bucket

    bucket Super Moderator Staff Member

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  5. 78c10bigten

    78c10bigten Full Access Member

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    I had the same problem on mine, i also ditched the 2 diaganol brackets that go to the top of the frame, partially due to going through 4 transmissions. But i had another set of headers from an old engine purchase that the collectors pointed down at more of an angle, i just used those and a sketchy looking adaptor.
     
  6. 75gmck25

    75gmck25 Full Access Member

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    I know that dual exhaust was a factory option, and have been told that there was a different W-shaped crossmember used with dual exhaust, but I've never actually seen one for a truck. I have seen performance crossmembers advertised for some older GM cars, but no listing for trucks.

    Transdapt also sells several universal crossmember kits, but I'm not sure what would work for our trucks.

    I also found this crossmember for 67-72 trucks. Maybe it can be adapted. http://www.classicperform.com/Store/1960_1972_Chevy_Truck/6372LDL.htm

    This one is supposed to be universal. http://www.classicperform.com/Store/1960_1972_Chevy_Truck/CP90171.htm

    Bruce
     
    Last edited: Oct 11, 2018
  7. smoothandlow84

    smoothandlow84 I'd rather be draggin' frame

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    With my long tube headers, had a shop bend exhaust piping to curve up and over the trans cross member on the passenger side. Its a tight fit, but it clears. My header flanges touch the pavement when the air is dumped from the air bags. 1513525692664.jpg
     
  8. Smindustries

    Smindustries Junior Member

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    Rusty Nail and 82sbshortbed like this.
  9. bucket

    bucket Super Moderator Staff Member

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    Two diagonal brackets? Does yours look like this:

    IMG_20180914_183809795.jpg
     
  10. 78c10bigten

    78c10bigten Full Access Member

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    Kinda but my "humps" that curve up are higher. Theres a pic of it somewhere in my media pages. I just tagged you in it
     
  11. bucket

    bucket Super Moderator Staff Member

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    Looks like your crossmember overall is higher, even at the trans mount? One thing to note is you appear to have actual truck headers. The car headers don't hang as low. So it may just be how it looks in the photo?

    20160529_145546.jpg
     
  12. bucket

    bucket Super Moderator Staff Member

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    And to the OP, the picture I posted showing the S-bends is on my C20 Burb. On my C10 that uses the crossmember like yours, I used the same type S-bends to run the exhaust ABOVE the crossmember, not below.
     
  13. 78c10bigten

    78c10bigten Full Access Member

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    My headers do drop past the frame. Maybe they are truck headers. Im not sure. The ones i was gunna use came off a 90' k10 gmt 400 that had a 76' 350 frankensteined into it but they were too close to the floor and wouldnt go under the cross member. These on it now came with the 350 i blew up previously so im not sure what theyre actully for but they were alot better fit. To look straight at them from behind without pipes on them they point more twords the ground and not flat
     
  14. bucket

    bucket Super Moderator Staff Member

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    Flowtech headers for our trucks have a slight downward angle to the collectors.
     

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